lower unit driveshaft bearing

Faztbullet

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Re: lower unit driveshaft bearing

On your set up all shims go under spacer and nothing goes on top of race except the water pump housing, and the bearing is upside down (numbers face pinion gear).
 

gwukena

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Re: lower unit driveshaft bearing

On your set up all shims go under spacer and nothing goes on top of race except the water pump housing, and the bearing is upside down (numbers face pinion gear).


So what preloads bearing? tapered roller bearing straight cut gears, no preload pin and why does my 83 115 have shims on both sides, when they are identical housings?
 

Faztbullet

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Re: lower unit driveshaft bearing

So what preloads bearing?
Bearings in a lower unit are not preloaded like a wheel bearing, they are shimmed to set correct backlash on gears. You shim the upper driveshaft bearing to get correct pinion height and backlash, the water pump housing holds this assembly in place.
why does my 83 115 have shims on both sides,
Dont know why but it is not correct, maybe wrong water pump base (lengths are different) and shimmed added to take up play???? The only units with shims on both sides where the early units using roller bearing held in place with c clip....
 

gwukena

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Re: lower unit driveshaft bearing

Bearings in a lower unit are not preloaded like a wheel bearing, they are shimmed to set correct backlash on gears. You shim the upper driveshaft bearing to get correct pinion height and backlash, the water pump housing holds this assembly in place.
,
Dont know why but it is not correct, maybe wrong water pump base (lengths are different) and shimmed added to take up play???? The only units with shims on both sides where the early units using roller bearing held in place with c clip....

Correct water pump base, I am installing a new one and have to add shims between base and bearing to make up for manufacturing tolerance (new base protrudes .015" less into housing). Appears some units did use shims on both sides (Cam shift 1 with old style driveshaft without preload pin). With the taper bearing setup on this unit and no preload pin in driveshaft, there is no way to control shaft endplay without shims between pump housing and bearing race. I attached excerpt from seloc manual. Parts breakdown shows shims either side.
bearing shimming.JPG
 

Faztbullet

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Re: lower unit driveshaft bearing

Parts breakdown shows shims either side.
Not a factory break down for that year unit....
With the taper bearing setup on this unit and no preload pin in driveshaft, there is no way to control shaft endplay without shims between pump housing and bearing race.
Have built 30-40 of these units over the years and never had to put shims under base....
 

gwukena

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Re: lower unit driveshaft bearing

Gwukena,
Yes this is my set up. I had the driveshaft bearing upside down. The manual isnt very helpful with this model as you said. Now I have to flip the bear around. Is there anyway to remove the bearing from driveshaft with breaking it? Thanks for all your help I was lost on this step and would of put it togather wrong if you didnt help me. Now to remove the bearing and start over. Thanks Again for your help.
Parker

Can you post pics of your setup? Apparently mine has been assembled wrong:facepalm:
 
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